BandWidth:Most hosting companies offer a variety of
bandwidth
options in their plans. So exactly what is bandwidth as it relates to
web hosting? Put simply, bandwidth is the amount of traffic that is
allowed to occur between your web site and the rest of the internet. The
amount of
bandwidth a hosting
company can provide is determined by their network connections, both
internal to their data center and external to the public internet.
Network Connectivity:The
internet, in the most simplest of terms, is a group of millions of
computers connected by networks. These connections within the internet
can be large or small depending upon the cabling and equipment that is
used at a particular internet location. It is the size of each network
connection that determines how much
bandwidth is available. For example, if you use a DSL connection to connect to the internet, you have 1.54 Mega bits (Mb) of
bandwidth.
Bandwidth therefore is measured in bits (a single 0 or 1). Bits are
grouped in bytes which form words, text, and other information that is
transferred between your computer and the internet.
If you have a DSL connection to the internet, you have dedicated
bandwidth
between your computer and your internet provider. But your internet
provider may have thousands of DSL connections to their location. All of
these connection aggregate at your internet provider who then has their
own dedicated connection to the internet (or multiple connections)
which is much larger than your single connection. They must have enough
bandwidth
to serve your computing needs as well as all of their other customers.
So while you have a 1.54Mb connection to your internet provider, your
internet provider may have a 255Mb connection to the internet so it can
accommodate your needs and up to 166 other users (255/1.54).
Traffic:A very simple analogy to use to understand
bandwidth and traffic is to think of highways and cars.
Bandwidth
is the number of lanes on the highway and traffic is the number of cars
on the highway. If you are the only car on a highway, you can travel
very quickly. If you are stuck in the middle of rush hour, you may
travel very slowly since all of the lanes are being used up.
Traffic
is simply the number of bits that are transferred on network
connections. It is easiest to understand traffic using examples. One
Gigabyte is 2 to the 30th power (1,073,741,824) bytes. One gigabyte is
equal to 1,024 megabytes. To put this in perspective, it takes one byte
to store one character. Imagine 100 file cabinets in a building, each of
these cabinets holds 1000 folders. Each folder has 100 papers. Each
paper contains 100 characters - A GB is all the characters in the
building. An MP3 song is about 4MB, the same song in wav format is about
40MB, a full length movie can be 800MB to 1000MB (1000MB = 1GB).
If
you were to transfer this MP3 song from a web site to your computer,
you would create 4MB of traffic between the web site you are downloading
from and your computer. Depending upon the network connection between
the web site and the internet, the transfer may occur very quickly, or
it could take time if other people are also downloading files at the
same time. If, for example, the web site you download from has a 10MB
connection to the internet, and you are the only person accessing that
web site to download your MP3, your 4MB file will be the only traffic on
that web site. However, if three people are all downloading that same
MP at the same time, 12MB (3 x 4MB) of traffic has been created. Because
in this example, the host only has 10MB of
bandwidth,
someone will have to wait. The network equipment at the hosting company
will cycle through each person downloading the file and transfer a
small portion at a time so each person's file transfer can take place,
but the transfer for everyone downloading the file will be slower. If
100 people all came to the site and downloaded the MP3 at the same time,
the transfers would be extremely slow. If the host wanted to decrease
the time it took to download files simultaneously, it could increase the
bandwidth of their internet connection (at a cost due to upgrading equipment).
Hosting Bandwidth:In
the example above, we discussed traffic in terms of downloading an MP3
file. However, each time you visit a web site, you are creating traffic,
because in order to view that web page on your computer, the web page
is first downloaded to your computer (between the web site and you)
which is then displayed using your browser software (Internet Explorer,
Netscape, etc.) . The page itself is simply a file that creates traffic
just like the MP3 file in the example above (however, a web page is
usually much smaller than a music file).
A
web page may be very small or large depending upon the amount of text
and the number and quality of images integrated within the web page. For
example, the home page for CNN.com is about 200KB (200 Kilobytes =
200,000 bytes = 1,600,000 bits). This is typically large for a web page.
In comparison, Yahoo's home page is about 70KB.
